A senior North Korean official began a five-day visit to China on Tuesday amid heightened tensions following North Korea's shelling of a South Korean island last week.

Chairman of North Korea's Supreme People's Assembly Choe Thae Bok arrived from Pyongyang, breezing past reporters at Beijing's Capital Airport without comment.

China's official Xinhua News Agency has said Choe was invited by China's second most powerful official, Wu Bangguo, and was expected to stay through Saturday.

Washington and Seoul have pressed China to use its influence on Pyongyang to ease tensions. China is impoverished North Korea's biggest benefactor and its only major ally.

Choe, who concurrently serves as a ruling Workers' Party secretary, was expected to meet top Chinese communist party officials and discuss last week's artillery barrage, the North's nuclear program and the U.S.-South Korean military drills, South Korea's Yonhap news agency reported.

Choe visited China in late September and briefed President Hu Jintao and other Chinese leaders about the North's decision to give top political posts to a son of North Korean leader Kim Jong Il, Yonhap said.